Re: degraded array - former device is unavailable

[Philip Ross <psr@warwickcompsoc.co.uk>]

Philip Ross wrote:
> I'm getting exactly the same problem after upgrading a test system from 
> Woody to Sarge. Every time I reboot the md raid1 root device is failing 
> to come up with both mirrors (see dmesg output below). When I add the 
> missing mirror manually using mdadm everything works fine up until the 
> next reboot.

I've fixed the issue now. The problem was that I had removed (with mdadm 
--fail) one of the mirrors prior to doing the upgrade.

When mkinitrd ran as part of installing the new kernel, it didn't detect 
both raid devices and only set up an initial ram disk capable of 
detecting one of the mirrors.

To fix, I added the missing mirror (with mdadm --add), waited for the 
raid device to sync up and then re-ran mkinitrd and lilo.

Phil